wood stove clearance confusion

[slugboy6000]

Hello, I should probably ask Jotul this question, but I didn't see any contact information on their website... so I thought I'd throw this one out there.

I'd like to install a small wood stove in the cottage I'm building. I'm trying to plan it's position so I can avoid joists and rafters, yet still keep the stove fairly close to the wall.

I've had my eye on the Jotul 602 CB, but their instruction manual is a little confusing.

The manual says that the clearance to combustibles is more when using double wall stove pipe (eg. 15" to the rear), then for single wall stove pipe (13.5"). It seems counter intuitive. Shouldn't double wall stove pipe radiate less, and require less clearance? Does the increased draft from the double wall pipe make the stove burn hotter??

((broken link removed to http://www.jotul.com/FileArchive/Technical%20Documentation/Wood%20Stoves/J%C3%B8tul%20F%20602%20CB/Manual_F_602_USA_P11_130412.pdf))

-Thanks for the help, and for the great resource!

 

[Highbeam]

Makes no sense, something is being read or written wrong.

 

[jeff_t]

Isn't that similar to ESW's deal? The double wall made it draft better and burn hotter. That's the way it tested, so that's how the manual is written.

 

[Wood Duck]

That sounds counter-intuitive to me, but I will say that I like the idea of at least a few inches extra clearance if at all possible. If at all possible I'd give it the larger clearance and then some.

 

[BrotherBart]

Yep. I think the manufacturers fall victim to the fact that there is so much variability when the outside labs do the cert. testing. Different day, different wood charge, maybe different guy firing the stove but the sensors are consistent.

But they have to publish the clearances the lab comes up with. In most cases the clearances are from the stove to the combustible surface, not the pipe.

 

[slugboy6000]

I didn't notice this at first,
With protected surfaces the logic reverses...the double wall stove pipe clearance is less than the single wall stove pipe.
I'll go with Wood Duck's advice and proceed with caution.

 

[dorkweed]

My 13NC is the same way with double walled stove pipe vs. single wall. I need greater clearance for the stove using double walled............but less for the stove and more for the pipe using single walled!

 

[Ashful]

Yep. I think the manufacturers fall victim to the fact that there is so much variability when the outside labs do the cert. testing. Different day, different wood charge, maybe different guy firing the stove but the sensors are consistent.

But they have to publish the clearances the lab comes up with. In most cases the clearances are from the stove to the combustible surface, not the pipe.

This is possible, but not likely. I deal with outside labs testing and certifying the equipment I design, and when they come back with senseless results, we go to the lab and figure out what they did wrong. It's a regular part of the business of designing certified product. Jotul would have to be incredibly lazy or foolish to accept numbers from a lab that disagree with their own in-house testing. Intuitive or not, the listed clearances are either a typo, or there's good reason for them.

 

[BrotherBart]

We do this conversation once or twice a year on the Englander stoves double wall clearances. They take what the lab says. And I ain't seen a lazy person down in Monroe yet.

MIke Holton the customer support manager at ESW replied to this previously.

"the diagram lists clearances that were specified by the testing agency for THE STOVE ONLY with no regard to the listings for the pipe. this means that the 18 inch clearance required for single wall pipe must be adhered to. so even theough the stove itself may be placed closer than 18 inches per the diagram it still cannot be that close due to the pipe. (personally i hate the way that diagram and clearance chart was done , but thats the way the testing agency said it had to be). now, as for the greater clearance with double wall pipe , double wall pipe retains more heat making the draft stronger , this makes the stove physically get hotter (or at least it did in testing , hence the greater required clearance.

i have to admit that the first time i read it i was on the phone to R/D with this same question , but it was explained to me then, and ive been explaining it ever since , i am pushing to get a more clear explanation as well as stove dimentions revised into the manual, they will likely be added in the next revision."